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FleaPlus writes "At the recent Joint Propulsion Conference, SpaceX's rocket development facility director Tom Markusic unveiled conceptual plans for how its current Falcon 1 and Falcon 9 commercial rockets can be evolved into heavy-lift rockets, ranging from a Falcon X capable of lifting 38,000kg to orbit, up to a 140,000kg Falcon XX (more than either the Saturn V or the 75,000kg shuttle-derived rocket Congress currently plans on having NASA spend >$13B building). SpaceX presentations also discuss a new Merlin 2 heavy-lift engine, solar-electric cargo tugs, adapting their current engines for descent/ascent vehicles fueled by Mars-derived methane, and a desire for the government to take the lead on in-space nuclear thermal propulsion while commercial focuses on launchers. In a recent interview, SpaceX CEO/CTO Elon Musk expressed his goal of lowering the price of Mars transportation enough to enable early colonization in 20 years, and his own plans for retiring to Mars."

Americans are taxed on citizenship, not residency. And, giving up citizenship for tax reasons is not as easy as you might think. However, there is the FEIE: Foreign Earned Income Exclusion, for monies earned outside the U.S. from non-U.S. sources, if you live outside the U.S. for a contiguous year or more. But, you don't have to go to Mars to take advantage of that.

I like nuclear thermal as much as the next/.er, but is there really any point in thermal rockets beyond attaining orbit?

For one thing there's the slight problem that you die during the transit through the Van Allen belts if you don't have a high-thrust engine or very large radiation shields.

And nuclear thermal rockets kind of suck ass for attaining orbit since you have to ensure that they land somewhere safe if they fail during launch; NASA's test plans for the early models involved polar launch where the flight path was designed to dump it in Antarctica or a remote part of the ocean if something went wrong.

As 0123456 indicated [slashdot.org], there are both a need for high thrust engines in space and huge risks with the use of nuclear-anything propulsion on Earth. In addition to passage through the Van Allen belts, we also need to consider the Oberth effect [wikipedia.org]. When you're trying to leave a gravity well (such as Earth's), then thrust deep in the well has a higher effective ISP than equivalent thrust higher up the well.

Second, because of the risks of operating nuclear rockets in Earth's biosphere, it makes sense, that if you're eventually going to have a nuclear powered rocket to orbit, that you try it somewhere else first and generate a reliability record. Space is the "somewhere else".

For space exploration to begin in earnest, we need it to be economically profitable, beyond LOE and geostationary. Has there been a study on the economic feasability of mining asteroids or something else (i.e. 4He on the moon)?

Yes, and as I understand it, the problem is that costs are a few zeroes greater than revenue. Something like SpaceX's new rocket can lop a zero off the costs, but we're going to need more than that before space mining makes economic sense. If they can lop off a second zero, say via high reusability and a launch rate of thousands of rockets a year, that might do.

I do believe he is referring to compton, CA. not exactly known to be a nicest collection of neighborhoods. I'm sure you wouldn't want to do any apple picking there, unless you like a not so healthy lead enriched diet.

Asteroid mining could be very profitable. According to Wikipedia [wikipedia.org], "At 1997 prices, a relatively small metallic asteroid with a diameter of 1 mile contains more than $20 trillion US dollars worth of industrial and precious metals." Of course, the value of the metal would go down as that one asteroid would add a huge amount to the supply, but still it would be a lot of money. A $1 trillion+ profit on a mission costing $10 billion would be a pretty good profit.

Also, "all the gold, cobalt, iron, manganese, molybdenum, nickel, osmium, palladium, platinum, rhenium, rhodium and ruthenium that we now mine from the Earth's crust, and that are essential for our economic and technological development, came originally from the rain of asteroids that hit the Earth after the crust cooled." So there's potentially a lot of valuable minerals out there waiting for us to exploit them.

I applaud the Obama administration for recognizing the awesomeness and redirecting funds from NASA Ares to Space-X.

Quick clarification: The White House hasn't proposed redirecting funds from Ares to SpaceX -- instead, they want to open up the US human spaceflight market to competing commercial vendors, which includes not just SpaceX, but also the United Launch Alliance. Many aren't familiar with the name, but the ULA builds the Atlas and Delta rockets which have launched most national security and NASA science missions for many years now. SpaceX has stated that they actually expect ULA to get more of the commercial crew market than them, at least initially.

Of course, even this is facing a great deal of friction in Congress. As one of the linked articles in the summary states, the current NASA bill in the House of Representatives has the entire commercial spaceflight program struggling with just $150M over 3 years, while the government-designed/operated heavy-lift and crew capsule program gets $13B over that same timeframe.

However, there is one key thing that SpaceX needs as they develop as a company. First, and foremost, SpaceX needs to get its LEO business to become lucrative and profitable. If that company can develop enough profit to start breaking away from NASA prize money and other political tie-ins, then they will be set.

Not sure if you already knew about this, but back in June SpaceX announced a huge launch contract with Iridium, which is the largest commercial launch contract in history (worth up to $492M). Of course, more contracts like that would be better, but change happens a step at a time.

Not in this case. By all accounts, Elon Musk didn't originally want to get into the rocket business. He wanted to be in the Mars colonization business, but quickly discovered that rockets were too damned expensive, so he decided to make his own.

For Musk, the marketing is a tool for achieving is vision, not the other way around.

It's actually quite interesting to read about Elon Musk's efforts to try to launch Mars Oasis and the "Life to Mars" foundation back in 2001, a year before he realized how screwed up the launch market was and decided to start SpaceX:

Someone is putting his money where my mouth has been. Describing permanent settlement of Mars as "a positive, constructive, inspirational goal" capable of uniting humanity at a critical time," dot-com entrepreneur Elon Musk has pledged a substantial portion of his personal fortune to realizing that goal, beginning with a proposed $20 million technology-demonstration Mars lander to be launched perhaps in 2005. Calling his "victory condition" seeing NASA's top priority change to establishing a permanent human presence on Mars, he said in an interview last week that "the path by which I hope to get there is to get the public enthusiastic about the possibility, then translate that into legislative pressure so that Congress hands us a Mars mandate." Musk's plans are invigorating, finally matching for Mars the initiative and boldness recently displayed in Low Earth Orbit by Dennis Tito's flight and the recent MirCorp announcement of a private "MiniMir" orbiting facility. I hope his entrepreneurial directness will bring a new effectiveness to the Mars effort. I hope also that he can avoid being brought down by the Byzantine politics of space: on the Hill, in the scientific community and in the space movement....

Musk's "Mars Oasis" project is a small robotic lander intended primarily as a mini-greenhouse, growing samples of food crops in an enclosed chamber filled with treated Martian regolith (soil), to test the feasibility of humans living off the land. Other experiments may include test units for the production of oxygen and rocket fuel from the Martian atmosphere, and radiation sensors. In a radical departure from the missions scheduled by NASA, each experiment would focus on developing data critical to human habitation, rather than on pure planetary science....

He refused to engage in political posturing or NASA-bashing, saying that "I don't have a palpable ideology for private or governmental missions." He described his relations with NASA as "good, I would say. I have not had any bad relations whatsoever. I don't see them as the bad guy. NASA's in the position it's in not through any desire of its own. The public is asking NASA often to have a perfect track record and a perfect safety record," yielding excessive caution and institutional gridlock. "By driving this private space mission forward," he continued, "I hope for changes for NASA, for it to receive a clear and pressing mandate for a human base [on Mars]. I want to reinvigorate NASA."

If I can boost some mining equipment to the Moon, and use one of those solar powered tugs to get my ore back to the LEO and drop it in the Ocean somewhere, eventually there would be a payoff.

And yes when you can throw something the size of the ISS up there in 3 launches, the long awaited microgravity manufacturing and some interesting vapor deposition electronics stuff with smaller whiskers and imperfections than you get on Earth are possible.

Maybe like the fly eyeballs nano solar cell story from last week, you only need the perfect space crap to build the molds, then make millions of widgets down on Earth where materials and labor costs are conventional.

Get the lift costs cheap enough and people will fill Bigelow Aerospace's hotels.

That's 50%; definitely not "put more rockets into the drink than it has into orbit."

Abysmal? I don't think so. That's pretty typical for national space programs during their first few attempts, and you'll notice they've had 3 successes in a row. This is rocket science, and IMO they're doing quite well.

As SpaceX and Musk should know, a modular system is a lot more flexible, and we know a lot more about how to design and build power reactors than nuclear thermal rockets. More to the point, you'd need a gas-core reactor to match the specific impulse of current VASIMR prototypes, and gas-core reactors are ENTIRELY theoretical.

A nuclear thermal rocket would be quite a bit more efficient in terms of mass than VASIMR. It's the difference between building a reactor that is a rocket engine and building a reactor plus a rocket engine.

Yeah, it's theoretical. But so is everything else about a Mars trip at this point.

As far as I'm aware nuclear thermal is a bad idea for a take off engine, it's comparatively low thrust even if it is high(er) ISP. Apart from Gas Cored rockets (which as you say are still science fiction at the moment) I've not seen a serious suggestion that Nuclear be used for takeof from earth (Nuclear salt rockets though for Mars takeoff could be interesting:-))

As I understand it where a Nuclear Thermal is good is where you need moderate thrust but for a long time, so they make a good 2nd stage engine or a great 3rd stage engine. The proposal as i understood it was to develop both nuclear reactors to supply power for ion engines and to develop nuclear thermal for the crew stage. As I understood the article this then meant you had 2 types of tugs, one ion engine based, and one nuclear thermal based. The first was used to get cargo from Earth to Mars using the least propellant, the second got your crew to Mars as quickly as possibly but at a lower fuel efficiency.As far as I was aware VASIMR is more theoretical than the straight Nuclear Thermal proposed here, so while a great design was a higher risk approach. Also because of it's multimode operation it was much harder to flight qualify and heavier so possibly not the best choice for the crew insertion mission.

The Falcon X vehicle is essentially a Saturn V replacement vehicle (rated to lift more tonnage but with less fuel). The Falcon XX.... if you look over the specs it turns out that it has the same cargo capacity as a 747 that would be used for inter-continental transport.

I don't know what you think could be flown on one of those vehicles, but those are simply huge and would require some customers wanting to put some serious tonnage into orbit. I like this analogy with the Falcon XX:

If you man-rated the FalconXX, you could put every astronaut who has ever flown into space so far in the entire history of mankind, together all at once, on a single flight into orbit. Yes, that would include food for a couple of days and life support. The size of that vehicle is something that has never flown... ever.

As far as what kind of equipment you would want to fly into space that could also barely fit into the cargo area of a 747-cargo plane, that would be an interesting prospect by itself. That goes way beyond GEO satellites or even a Hubble replacement, but more along the lines of a monster spacecraft built by Bigelow that could hold a couple thousand people. I am still trying to get my head around how big that vehicle is and what kind of applications it would be used for.